Sheet composition



to provide an improved Fatented eb. W, 1925 rarss rnenn r. timer, or an, onto.

SHEET UGBIPQSITIGEE.

EIe FDrawing.

To all whom it may concern:

Be it known that l, FRANK T. Lamar,

a citizen of the United States of America,

sition, and the process of manufacturing the same.

More particularly, the invention has relation to a process for the utilization of waste material, such as waste unvulcanized or uncured rubber fabric.-

One important object of the invention is rocess for manu facturing a sheet materia from waste products combined in a novel manner.

A second im ortant object or" the invention is the pro notion of an improved sheet material made from waste material, the principal materials being waste paper and waste rubber.

lln carrying out the objects of this invention, the preferred manner of producing the sheet material, is as follows.

Sufficient of the waste material is fixed in the following proportions, and in the following way:

To each four ounces of paper board, or

aper pulp and waste paper, there is added bur ounces of rubber or rubber fabric ot the kind known as uncured friction, or rubber fabric which consists of rubber with a fabric or fiber incorporated therein, or a mixture, of four ounces of rubber with fiber may e utilized. The batch consisting of these. ingredients is then placed upon a washing machine, either of the type provided with corrugated rolls, or of the type provided with smooth rolls moving at (11fferent speeds, and is passed through these rolls so as to thoroughly and intimately knead the ingredients together, and the materials being slightly molstened with water, or preferab y an emulsion of various kinds of oils, either vegetable, animal or mineral. After this then dried, there is added to this treated rubber waste in the proportion of four ounces to eacheightounces of the mixture, this rubber waste being treated in the manner described in my prior Patent 1,233,-

252, of July 10, 1917. The entire batch is then placed in a mixing material, and varibatch is intimately mixed and Application filed March at, 19%. Serial 130. $28,512.

ous oxides added thereto, or these oxides 'may be replaced by suitable-mineral substances, these substances acting as fillers. As the examples of such substances, there may be used fossil flour, magnesia, magnesite, fullers earth, zinc oxide, or other similar substances. Sulphur is also added according to the degree of hardness required in the resultant product. After themixing, the material is then rolled to proper sheet form and vulcanized to the required degree of hardness, this depending of course on the sulphur content.

As an alternative manner oi preparing such sheets, I my mix together two pounds of crude rubber, from two to four ounces of oleaginous substance, either in solid or liquid condition, these ingredients being heated suihciently to liqueiy the solids. To the, batch thus formed, I add from four to six pounds of paper pulp in a damp condition, preferably using paper pulp which has been pulped on a washing machine by the aid of water. As an alternative to the paper pulp, I may add raw vegetable substances containing cellulose. lhese substances are thoroughly mixed in a mixing machine, and may also have suitable fillers, and a required quantity of sulphur for hardening purposes added thereto. The subsequent treatment after consists in rolling into sheets and vulcanizing as desired.

The resultant product from either of these alternatives may be manufactured into a variety of articles, such as roofing sheets or tiles, in which case the material is left more or less soft and pliable, into boxes in which case the vulcanization is carried to a point where the articles are hard and re-. sistant, and in fact into a wide variety of products.

There has thus been provided a novel and improved product, and a novel process of manufacturing the same.

I claim:

. 1. The process of manufacturing a composition which consists in intimately mixing equal parts of paper pulp and uncured waste rubber fabric in combination with a moistening material, adding to the mixed batch a quantity of treated rubber waste equal to one-half the quantity of the batch and thoroughly mixing the entire mass toother with an inert mineral filler to which has been added sulphur in desired quantities for vulcanizing, rolling the mass into sheets, and finally vulcanizing the rolled sheets.

2. The process of preparing a composition of the class described which consists in mixing equal quantities of waste from paper manufacture and uncured rubber "fabric together with an oil emulsion, drying the mess, adding to the dried mass a quantity wee eee of treated rubber waste equal in quantity to the uncured rubber fabric, mixing the entire batch intimately with the addition of sulphur to a quantity sufficient to produce desired vulcanization, rolling the mixture into sheets, and vulcanizing the sheets.

In testimony whereof I afiix my signature.

FRANK T. LAHEY. 

